Study: Illegal Immigrant Population Shrinks, Crossings Down Sharply

WASHINGTON, Sept. 1, 2010— -- The number of illegal immigrants in the United States has begun to shrink, ending two decades of steady growth, according to a new study by the Pew Hispanic Center.

An estimated 11.1 million illegal immigrants lived across the United States as of March 2009, down nearly 8 percent from a peak of 12 million in 2007. Still, the unauthorized population remains a third larger than it was in 2000.

"This is something we haven't seen before," Jeffrey Passel, a senior Pew demographer, said of the decline. "It's a rather large decline and sustained over two years."

Passel attributed the new trend to a sharp decrease in the number of illegal immigrants crossing U.S. borders in recent years.

The in-flow of unauthorized immigrants averaged 500,000 per year for the first half of the decade, but plummeted to an estimated 150,000 a year between 2007 and 2009, according to the report.

"There is constant in and out movement among immigrants," Passel said. "But what's changed most is the number coming in."

While the study does not identify reasons for the decline, experts say stepped up enforcement of immigration laws and enhanced border security measures have contributed to the change.

Over the past decade, lawmakers have approved funding for more border patrol agents, construction of hundreds of miles of border "fence," deployment of unmanned aerial drones and new systems for employers to verify the legal status of immigrant workers.

Immigration and Customs Enforcement has detained and deported an increasing number of illegal immigrants since 2001, removing 387,000 last year alone -- a seventh consecutive record high.

But the U.S. economic downturn has also played a key role in mitigating the incentive for prospective illegal migrants, who typically come in search of money and jobs.

"Because it's harder to get in and when you get in you may not be able to find a job, fewer appear to be trying," Passel said.